The constitution of the World Health Organization had been signed by 61 countries on 22 July 1946, with the first meeting of the World Health Assembly finishing on 24 July 1948. It incorporated the Office international d'hygiène publique and the League of Nations Health Organization. Since its creation, it has played a leading role in the eradication of smallpox. Its current priorities include communicable diseases, in particular HIV/AIDS, Ebola, malaria and tuberculosis; the mitigation of the effects of non-communicable diseases; sexual and reproductive health, development, and aging; nutrition, food security and healthy eating; occupational health; substance abuse; and driving the development of reporting, publications, and networking.

During the 1945 United Nations Conference on International Organization, Dr. Szeming Sze, a delegate from China, conferred with Norwegian and Brazilian delegates on creating an international health organization under the auspices of the new United Nations. After failing to get a resolution passed on the subject, Alger Hiss, the Secretary General of the conference, recommended using a declaration to establish such an organization. Dr. Sze and other delegates lobbied and a declaration passed calling for an international conference on health.[2] The use of the word "world", rather than "international", emphasized the truly global nature of what the organization was seeking to achieve.[3] The constitution of the World Health Organization was signed by all 51 countries of the United Nations, and by 10 other countries, on 22 July 1946.[4] It thus became the first specialised agency of the United Nations to which every member subscribed.[5] Its constitution formally came into force on the first World Health Day on 7 April 1948, when it was ratified by the 26th member state.[6] The first meeting of the World Health Assembly finished on 24 July 1948, having secured a budget of US$5 million (then GBP£1,250,000) for the 1949 year. Andrija Stampar was the Assembly's first president, and G. Brock Chisholm was appointed Director-General of WHO, having served as Executive Secretary during the planning stages.[3] Its first priorities were to control the spread of malaria, tuberculosis and sexually transmitted infections, and to improve maternal and child health, nutrition and environmental hygiene. Its first legislative act was concerning the compilation of accurate statistics on the spread and morbidity of disease.[3] The logo of the World Health Organization features the Rod of Asclepius as a symbol for healing.[7]

In 1958, Viktor Zhdanov, Deputy Minister of Health for the USSR, called on the World Health Assembly to undertake a global initiative to eradicate smallpox, resulting in Resolution WHA11.54.[9] At this point, 2 million people were dying from smallpox every year. In 1967, the World Health Organization intensified the global smallpox eradication by contributing $2.4 million annually to the effort and adopted a new disease surveillance method.[10][11] The initial problem the WHO team faced was inadequate reporting of smallpox cases. WHO established a network of consultants who assisted countries in setting up surveillance and containment activities.[12] The WHO also helped contain the last European outbreak in Yugoslavia in 1972.[13] After over two decades of fighting smallpox, the WHO declared in 1979 that the disease had been eradicated – the first disease in history to be eliminated by human effort.[14]

In 1998, WHO's Director General highlighted gains in child survival, reduced infant mortality, increased life expectancy and reduced rates of "scourges" such as smallpox and polio on the fiftieth anniversary of WHO's founding. He, did, however, accept that more had to be done to assist maternal health and that progress in this area had been slow.[15]Cholera and malaria have remained problems since WHO's founding, although in decline for a large part of that period.[16] In the twenty-first century, the Stop TB Partnership was created in 2000, along with the UN's formulation of the Millennium Development Goals. The Measles initiative was formed in 2001, and credited with reducing global deaths from the disease by 68% by 2007. In 2002, The Global Fund to Fight AIDS, Tuberculosis and Malaria was drawn up to improve the resources available.[8] In 2006, the organization endorsed the world's first official HIV/AIDS Toolkit for Zimbabwe, which formed the basis for a global prevention, treatment and support plan to fight the AIDS pandemic.[17]

The WHO's Constitution states that its objective "is the attainment by all people of the highest possible level of health".[18]

WHO fulfills its objective through its functions as defined in its Constitution: (a) to act as the directing and co-ordinating authority on international health work (b) to establish and maintain effective collaboration with the United Nations, specialized agencies, governmental health administrations, professional groups and such other organizations as may be deemed appropriate (c) to assist Governments, upon request, in strengthening health services (d) to furnish appropriate technical assistance and, in emergencies, necessary aid upon the request or acceptance of Governments (e) to provide or assist in providing, upon the request of the United Nations, health services and facilities to special groups, such as the peoples of trust territories (f) to establish and maintain such administrative and technical services as may be required, including epidemiological and statistical services (g) to stimulate and advance work to eradicate epidemic, endemic and other diseases (h) to promote, in co-operation with other specialized agencies where necessary, the prevention of accidental injuries (i) to promote, in co-operation with other specialized agencies where necessary, the improvement of nutrition, housing, sanitation, recreation, economic or working conditions and other aspects of environmental hygiene (j) to promote co-operation among scientific and professional groups which contribute to the advancement of health (k) to propose conventions, agreements and regulations, and make recommendations with respect to international health matters and to perform.

The 2012–2013 WHO budget identified 5 areas among which funding was distributed.[21] Two of those five areas related to communicable diseases: the first, to reduce the "health, social and economic burden" of communicable diseases in general; the second to combat HIV/AIDS, malaria and tuberculosis in particular.[21]

In terms of HIV/AIDS, WHO works within the UNAIDS network and considers it important that it works in alignment with UNAIDS objectives and strategies. It also strives to involve sections of society other than health to help deal with the economic and social effects of the disease.[22] In line with UNAIDS, WHO has set itself the interim task between 2009 and 2015 of reducing the number of those aged 15–24 years who are infected by 50%; reducing new HIV infections in children by 90%; and reducing HIV-related deaths by 25%.[23]

Although WHO dropped its commitment to a global malaria eradication campaign in the 1970s as too ambitious, it retains a strong commitment to malaria control. WHO's Global Malaria Programme works to keep track of malaria cases, and future problems in malaria control schemes. WHO is to report, likely in 2015, as to whether RTS,S/AS01, currently in research, is a viable malaria vaccine. For the time being, insecticide-treated mosquito nets and insecticide sprays are used to prevent the spread of malaria, as are antimalarial drugs – particularly to vulnerable people such as pregnant women and young children.[24]

WHO's help has contributed to a 40% fall in the number of deaths from tuberculosis between 1990 and 2010, and since 2005, it claims that over 46 million people have been treated and an estimated 7 million lives saved through practices advocated by WHO. These include engaging national governments and their financing, early diagnosis, standardising treatment, monitoring of the spread and impact of tuberculosis and stabilising the drug supply. It has also recognised the vulnerability of victims of HIV/AIDS to tuberculosis.[25]

The WHO estimates that 12.6 million people died as a result of living or working in an unhealthy environment in 2012 – this accounts for nearly 1 in 4 of total global deaths. Environmental risk factors, such as air, water and soil pollution, chemical exposures, climate change, and ultraviolet radiation, contribute to more than 100 diseases and injuries. This can result in a number of pollution-related diseases.

It also tries to prevent or reduce risk factors for "health conditions associated with use of tobacco, alcohol, drugs and other psychoactive substances, unhealthy diets and physical inactivity and unsafe sex".[21][29][30]

The WHO promotes road safety as a means to reduce traffic-related injuries.[31]

WHO has also worked on global initiatives in surgery, including emergency and essential surgical care,[32] trauma care,[33] and safe surgery.[34] The WHO Surgical Safety Checklist is in current use worldwide in the effort to improve patient safety.[35]

The World Health Organization's primary objective in natural and man-made emergencies is to coordinate with Member States and other stakeholders to "reduce avoidable loss of life and the burden of disease and disability."[21]

On 5 May 2014, WHO announced that the spread of polio is a world health emergency – outbreaks of the disease in Asia, Africa and the Middle East are considered "extraordinary".[36][37]

On 8 August 2014, WHO declared that the spread of Ebola is a public health emergency; an outbreak which is believed to have started in Guinea, has spread to other nearby countries such as Liberia and Sierra Leone. The situation in West Africa is considered very serious.[38]

WHO addresses government health policy with two aims: firstly, "to address the underlying social and economic determinants of health through policies and programmes that enhance health equity and integrate pro-poor, gender-responsive, and human rights-based approaches" and secondly "to promote a healthier environment, intensify primary prevention and influence public policies in all sectors so as to address the root causes of environmental threats to health".[21]

In terms of health services, WHO looks to improve "governance, financing, staffing and management" and the availability and quality of evidence and research to guide policy making. It also strives to "ensure improved access, quality and use of medical products and technologies".[21] WHO - working with donor agencies and national governments - can improve their use of and their reporting about their use of research evidence.[43]

The remaining two of WHO's thirteen identified policy areas relate to the role of WHO itself:[21]

"to provide leadership, strengthen governance and foster partnership and collaboration with countries, the United Nations system, and other stakeholders in order to fulfill the mandate of WHO in advancing the global health agenda"; and

"to develop and sustain WHO as a flexible, learning organization, enabling it to carry out its mandate more efficiently and effectively".

The WHO along with the World Bank constitute the core team responsible for administering the International Health Partnership (IHP+). The IHP+ is a group of partner governments, development agencies, civil society and others committed to improving the health of citizens in developing countries. Partners work together to put international principles for aid effectiveness and development cooperation into practice in the health sector.[44]

As part of the United Nations, the World Health Organization supports work towards the Millennium Development Goals.[51] Of the eight Millennium Development Goals, three – reducing child mortality by two-thirds, to reduce maternal deaths by three-quarters, and to halt and begin to reduce the spread of HIV/AIDS – relate directly to WHO's scope; the other five inter-relate and have an impact on world health.[52]

The World Health Organization works to provide the needed health and well-being evidence through a variety of data collection platforms, including the World Health Survey covering almost 400,000 respondents from 70 countries,[53] and the Study on Global Ageing and Adult Health (SAGE) covering over 50,000 persons over 50 years old in 23 countries.[54] The Country Health Intelligence Portal (CHIP), has also been developed to provide an access point to information about the health services that are available in different countries.[55] The information gathered in this portal is utilized by the countries to set priorities for future strategies or plans, implement, monitor, and evaluate it.

The WHO has published various tools for measuring and monitoring the capacity of national health systems[56] and health workforces.[57] The Global Health Observatory (GHO) has been the WHO's main portal which provides access to data and analyses for key health themes by monitoring health situations around the globe.[58]

The WHO Assessment Instrument for Mental Health Systems (WHO-AIMS), the WHO Quality of Life Instrument (WHOQOL), and the Service Availability and Readiness Assessment (SARA) provide guidance for data collection.[59] Collaborative efforts between WHO and other agencies, such as through the Health Metrics Network, also aim to provide sufficient high-quality information to assist governmental decision making.[60] WHO promotes the development of capacities in member states to use and produce research that addresses their national needs, including through the Evidence-Informed Policy Network (EVIPNet).[61] The Pan American Health Organization (PAHO/AMRO) became the first region to develop and pass a policy on research for health approved in September 2009.[62]

On 10 December 2013, a new WHO database, known as MiNDbank, went online. The database was launched on Human Rights Day, and is part of WHO's QualityRights initiative, which aims to end human rights violations against people with mental health conditions. The new database presents a great deal of information about mental health, substance abuse, disability, human rights, and the different policies, strategies, laws, and service standards being implemented in different countries.[63] It also contains important international documents and information. The database allows visitors to access the health information of WHO member states and other partners. Users can review policies, laws, and strategies and search for the best practices and success stories in the field of mental health.[63]

WHO Member States appoint delegations to the World Health Assembly, WHO's supreme decision-making body. All UN Member States are eligible for WHO membership, and, according to the WHO web site, "other countries may be admitted as members when their application has been approved by a simple majority vote of the World Health Assembly".[70]

The World Health Assembly is the legislative and supreme body of WHO. Based in Geneva, it typically meets yearly in May. It appoints the Director-General every five years, and votes on matters of policy and finance of WHO, including the proposed budget. It also reviews reports of the Executive Board and decides whether there are areas of work requiring further examination. The Assembly elects 34 members, technically qualified in the field of health, to the Executive Board for three-year terms. The main functions of the Board are to carry out the decisions and policies of the Assembly, to advise it and to facilitate its work.[74]

The regional divisions of WHO were created between 1949 and 1952, and are based on article 44 of WHO's constitution, which allowed the WHO to "establish a [single] regional organization to meet the special needs of [each defined] area". Many decisions are made at regional level, including important discussions over WHO's budget, and in deciding the members of the next assembly, which are designated by the regions.[75]

Each region has a Regional Committee, which generally meets once a year, normally in the autumn. Representatives attend from each member or associative member in each region, including those states that are not fully recognised. For example, Palestine attends meetings of the Eastern Mediterranean Regional office. Each region also has a regional office.[75] Each Regional Office is headed by a Regional Director, who is elected by the Regional Committee. The Board must approve such appointments, although as of 2004, it had never overruled the preference of a regional committee. The exact role of the board in the process has been a subject of debate, but the practical effect has always been small.[75] Since 1999, Regional Directors serve for a once-renewable five-year term.[76]

Each Regional Committee of the WHO consists of all the Health Department heads, in all the governments of the countries that constitute the Region. Aside from electing the Regional Director, the Regional Committee is also in charge of setting the guidelines for the implementation, within the region, of the health and other policies adopted by the World Health Assembly. The Regional Committee also serves as a progress review board for the actions of WHO within the Region.

The Regional Director is effectively the head of WHO for his or her Region. The RD manages and/or supervises a staff of health and other experts at the regional offices and in specialized centers. The RD is also the direct supervising authority—concomitantly with the WHO Director-General—of all the heads of WHO country offices, known as WHO Representatives, within the Region.

*Acting Director-General following the death of Lee Jong-wook while in office

The head of the organization is the Director-General, elected by the World Health Assembly.[74] The current Director-General is Margaret Chan, who was first appointed on 9 November 2006[84] and confirmed for a second term until the end of June 2017.[85]

WHO employs 8,500 people in 147 countries.[86] In support of the principle of a tobacco-free work environment the WHO does not recruit cigarette smokers.[87] The organization has previously instigated the Framework Convention on Tobacco Control in 2003.[88]

The country office is headed by a WHO Representative (WR). As of 2010[update], the only WHO Representative outside Europe to be a national of that country was for the Libyan Arab Jamahiriya ("Libya"); all other staff were international. Those in the Region for the Americas, they are referred to as PAHO/WHO Representatives. In Europe, WHO Representatives also serve as Head of Country Office, and are nationals with the exception of Serbia; there are also Heads of Country Office in Albania, the Russian Federation, Tajikistan, Turkey, and Uzbekistan.[92] The WR is member of the UN system country team which is coordinated by the UN System Resident Coordinator.

The country office consists of the WR, and several health and other experts, both foreign and local, as well as the necessary support staff.[90] The main functions of WHO country offices include being the primary adviser of that country's government in matters of health and pharmaceutical policies.[93]

The WHO is financed by contributions from member states and outside donors. As of 2012[update], the largest annual assessed contributions from member states came from the United States ($110 million), Japan ($58 million), Germany ($37 million), United Kingdom ($31 million) and France ($31 million).[94] The combined 2012–2013 budget has proposed a total expenditure of $3,959 million, of which $944 million (24%) will come from assessed contributions. This represented a significant fall in outlay compared to the previous 2009–2010 budget, adjusting to take account of previous underspends. Assessed contributions were kept the same. Voluntary contributions will account for $3,015 million (76%), of which $800 million is regarded as highly or moderately flexible funding, with the remainder tied to particular programmes or objectives.[95]

In 1959, the WHO signed Agreement WHA 12–40 with the International Atomic Energy Agency (IAEA). The agreement states that the WHO recognises the IAEA as having responsibility for peaceful nuclear energy without prejudice to the roles of the WHO of promoting health. However, the following paragraph adds that "whenever either organization proposes to initiate a programme or activity on a subject in which the other organization has or may have a substantial interest, the first party shall consult the other with a view to adjusting the matter by mutual agreement".[100] The nature of this statement has led some pressure groups and activists (including Women in Europe for a Common Future) to believe that the WHO is restricted in its ability to investigate the effects on human health of radiation caused by the use of nuclear power and the continuing effects of nuclear disasters in Chernobyl and Fukushima. They believe WHO must regain what they see as "independence".[101][102][103]

In 2003, the WHO denounced the Roman Curia's health department's opposition to the use of condoms, saying: "These incorrect statements about condoms and HIV are dangerous when we are facing a global pandemic which has already killed more than 20 million people, and currently affects at least 42 million."[104] As of 2009[update], the Catholic Church remains opposed to increasing the use of contraception to combat HIV/AIDS.[105] At the time, the World Health Assembly President, Guyana's Health Minister Leslie Ramsammy, condemned Pope Benedict's opposition to contraception, saying he was trying to "create confusion" and "impede" proven strategies in the battle against the disease.[106]

Some of the research undertaken or supported by WHO to determine how people's lifestyles and environments are influencing whether they live in better or worse health can be controversial, as illustrated by a 2003 joint WHO/FAO report on nutrition and the prevention of chronic non-communicable disease,[108] which recommended that sugar should form no more than 10% of a healthy diet. The report led to lobbying by the sugar industry against the recommendation, to which the WHO/FAO responded by including in the report this statement: "The Consultation recognized that a population goal for free sugars of less than 10% of total energy is controversial". It also stood by its recommendation based upon its own analysis of scientific studies.[109] In 2014, WHO reduced recommended sugar levels by half and said that sugar should make up no more than 5% of a healthy diet.[110]

By the post-pandemic period critics claimed the WHO had exaggerated the danger, spreading "fear and confusion" rather than "immediate information".[111] Industry experts countered that the 2009 pandemic had led to "unprecedented collaboration between global health authorities, scientists and manufacturers, resulting in the most comprehensive pandemic response ever undertaken, with a number of vaccines approved for use three months after the pandemic declaration. This response was only possible because of the extensive preparations undertaken in during the last decade".[112]

Following the 2014 Ebola outbreak in West Africa, the organization was heavily criticized for its bureaucracy, insufficient financing, regional structure, and staffing profile.[113]

An internal WHO report on the Ebola response pointed to underfunding and lack of "core capacity" in health systems in developing countries as the primary weaknesses of the existing system. At the annual World Health Assembly in 2015, Director General Margaret Chan announced a $100 million Contingency Fund for rapid response to future emergencies,[114][115] of which it had received $26.9 million by April 2016 (for 2017 disbursement). WHO has budgeted an additional $494 million for its Health Emergencies Programme in 2016-17, for which it had received $140 million by April 2016.[116]

The program was aimed at rebuilding WHO capacity for direct action, which critics said had been lost due to budget cuts in the previous decade that had left the organization in an advisory role dependent on member states for on-the-ground activities. In comparison, billions of dollars have been spent by developed countries on the 2013-16 Ebola epidemic and 2015-16 Zika epidemic.[117]

The WHO has a Framework Convention on Tobacco implementation database which is one of the only mechanisms to help enforce compliance with the FCTC.[118] However, there has been reports of numerous discrepancies between it and national implementation reports on which it was built. As researchers Hoffman and Rizvi report "As of July 4, 2012, 361 (32·7%) of 1104 countries' responses were misreported: 33 (3·0%) were clear errors (eg, database indicated “yes” when report indicated “no”), 270 (24·5%) were missing despite countries having submitted responses, and 58 (5·3%) were, in our opinion, misinterpreted by WHO staff".[119]

^Hoffman S.J.; Røttingen J-A. (2012). "Assessing Implementation Mechanisms for an International Agreement on Research and Development for Health Products". Bulletin of the World Health Organization. 90 (12): 854–863. doi:10.2471/BLT.12.109827.